CN119122462A - A tool and method for repairing annular pressure - Google Patents

Abstract

The present invention discloses a tool and method for repairing annular pressure. The tool comprises: a main body and a drilling assembly, a hole-opening assembly, a repair assembly and a first sealing device arranged on the main body from top to bottom in sequence; the hole-opening assembly is used to open holes in the production casing; the drilling assembly is used to drill the cement ring through the holes to form a repair channel; the repair assembly comprises: a heater and a starter; the heater is arranged in the first cavity of the main body and forms a storage mechanism with the main body; the storage mechanism is used to store fusible metal blocks and is connected to the outside; the heater is used to hold heating fuel; the starter is arranged at the top of the heater to start and activate the heating fuel based on a start signal transmitted from the outside, and then melt the fusible metal block by heating the fuel to form a metal fluid; the first sealing device is used to fix the tool position, and allow the metal fluid flowing out of the storage mechanism to enter the repair channel through the hole under the blockage of the first sealing device. It can improve the repair effect.

Description

Tool and method for repairing annular pressure

Technical Field

The invention relates to the technical field of oil and gas well completion, in particular to a tool and a method for repairing annular space with pressure.

Background

With the continuous development of oil and gas exploration and development work, the exploitation of natural gas reservoirs is increasingly receiving attention from various countries. At present, the exploitation depth of natural gas wells is continuously increased, but most of the natural gas wells are faced with severe environments such as underground high temperature and high pressure and even corrosive gas, and the problems of annulus pressure are commonly existed in the high temperature and high pressure gas wells.

The problem of annular space with pressure is very unfavorable for safe production, and is a common problem in the petroleum industry. The annular space with pressure can reduce the recovery ratio of the gas well, seriously affect the yield of the gas well, and can have adverse effects on subsequent operations of gas field development, such as acid fracturing and the like. When the annular pressure is not obvious, the cost of wellhead annular pressure monitoring and pressure release will rise, and when serious, well closing and whole well discarding can be caused. For example, in a region, many of 18000 wells with pressure in the annulus of the surface casing must be shut in, and some wells may even need to be shut in.

The primary reasons for the creation of annular pressure in a gas well are two, tubing string failure, typically in the form of a threaded connection to the tubing string and packer seal failure, resulting in production zone gas channeling to the oil casing annulus (annulus a) and accumulation at the wellhead creating annular pressure. The method is successfully applied to the gulf of mexico, the netherlands, the Louisiana of the U.S. and the Kazakhstan and the Australia, and has higher success rate and lower cost, and the cement ring is in sealing failure, and because of the existence of a plurality of tiny gaps inside the cement ring, the high-pressure gas under the well can permeate to the wellhead of the annular space (annular space) of the sleeve along the gaps, so that the annular space is pressurized. The later treatment generally needs to make the plugging agent enter a gas channeling passage in a perforation, plugging agent squeezing and baffle beating mode, and a partition is formed after the plugging agent is solidified to treat annular space with pressure, wherein the plugging agent used in the prior art is generally cement or resin.

Disclosure of Invention

The inventor of the application discovers that the existing method for solving the problem of annular space belt pressure caused by cement sheath sealing failure has the defects that the problem of annular space belt pressure still exists after plugging operation due to the fact that gas channeling channels in cement sheath are randomly distributed and the gas channeling channels which cannot be hit by perforation are limited, when the plugging agent used for plugging in the prior art is cement slurry, the cement slurry has the problems of poor fluidity and difficulty in extruding micro cracks, the cement is easily corroded by underground corrosive gas, new cracks possibly occur after a period of time to cause annular space belt pressure, the plugging effect is poor, and the resin has strong permeability but needs longer solidification time, so that the sealing effect is poor, the construction period is long and the like in the sealing failure mode of the cement sheath is solved in the prior art.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a tool and a method for repairing annular pressure that overcomes or at least partially solves the above problems.

The embodiment of the invention provides a tool for repairing annular space with pressure, which comprises a body, a drilling assembly, an opening assembly, a repairing assembly and a first setting device, wherein the drilling assembly, the opening assembly, the repairing assembly and the first setting device are sequentially arranged on the body from top to bottom;

the perforating assembly is used for perforating the production sleeve;

The drilling assembly is used for drilling the cement sheath through the hole to form a repairing pore canal;

The repair assembly includes a heater and a starter;

The heater is arranged in the first cavity of the body, and a storage mechanism is formed between the heater and the body;

The device comprises a storage mechanism, a heater, a starter, a heating device and a control unit, wherein the storage mechanism is used for storing a fusible metal block and is communicated with the outside;

The first setting device is used to fix the tool position and allow the metal fluid flowing from the reservoir to enter the repair channel through the aperture under the barrier of the first setting device.

In an alternative embodiment, the upper end surface of the body is provided with at least one fluid inlet, and the side wall is provided with a fluid outlet corresponding to the fluid inlet;

the drilling assembly comprises a fluid flow passage for communicating the fluid inlet with a corresponding fluid outlet, a universal shaft and a turbine which are arranged in the fluid, and a drilling bit connected to the front end of the universal shaft;

the turbine is sleeved on the universal shaft, so that the universal shaft and the drilling bit are driven to move under the action of hydraulic pressure, and the cement sheath is drilled through the hole to form a repairing pore canal.

In an alternative embodiment, the fusible metal mass comprises a binary eutectic alloy of bismuth and germanium, a binary eutectic alloy of bismuth and copper, a binary eutectic alloy of bismuth and tin, or a binary eutectic alloy of bismuth and silver.

In an alternative embodiment, the heating fuel comprises thermite powder and thermite pellets;

The thermite medicine block is stacked in the heater, and the thermite powder is arranged at the top of the thermite medicine block, so that the thermite powder is excited by the starter to generate high-temperature ignition for the thermite medicine block.

In an alternative embodiment, the lower end of the first cavity is provided with a screen, and the storage mechanism is communicated with the outside through the screen;

accordingly, the metal fluid flows out of the storage mechanism through the screen.

In an alternative embodiment, the fluid flow channel comprises a direct current section, a conical section and a bending section which are connected in sequence from top to bottom;

The direct current section is connected with one end of the conical section with larger diameter, and the bending section is connected with one end of the conical section with smaller diameter;

the turbine is in threaded engagement with the inner wall of the direct current section, and the conical section is used for limiting the downward movement of the turbine.

In an alternative embodiment, the inner part of the universal joint of the universal shaft is provided with flow passages which are communicated with each other;

The drilling bit is a diamond-embedded bit, and a nozzle is arranged in the center of the drilling bit.

In an alternative embodiment, the opening assembly is arranged in the second cavity of the body and comprises an opening drill bit, a drill rod, a hydraulic device and a screw motor;

a window which can be used for the drill rod to extend out is formed in the side wall of the body;

One end of the drill rod is connected with the perforating drill bit, the other end of the drill rod is connected with a piston rod of a hydraulic device so as to drive the drill rod to move through the hydraulic device, and the side wall of the drill rod is meshed with a screw gear of the screw motor so as to drive the drill rod to rotate through the screw motor.

In an alternative embodiment, the diameter of the hole drill bit is greater than the diameter of the drill bit.

In an alternative embodiment, the inner bore of the guide communicates with the flow passage to guide the movement of the cardan shaft.

In an alternative embodiment, the center line of the inner hole of the guide is set at a preset included angle with the center line of the body.

In an alternative embodiment, the repairing annular space tool provided by the embodiment of the invention further comprises a second setting device and a third setting device;

The second setting device is arranged at the upper end of the body, and the third setting device is arranged between the opening assembly and the repairing assembly.

Based on the same inventive concept, the embodiment of the invention also provides a repairing method for realizing annular pressure based on the tool for repairing annular pressure, which comprises the following steps:

lowering the tool to a first preset position in the production casing, and after setting the tool, opening at least one hole in the production casing by using the opening assembly;

After the perforated hole of the sleeve is processed, the tool setting is released, the tool is controlled to move downwards to a second preset position, the tool is set, and a drilling component is utilized to drill out the cement sheath through the perforation to form a repairing pore canal;

After the drilling of the repairing hole channel is completed, the tool setting is released, the tool is lifted to a third preset position, the first setting device is used for fixing the tool position, a heating component is used for heating and melting a fusible metal block in the storage mechanism to form a metal fluid, and after the metal fluid flows out of the storage mechanism, the metal fluid flows into a repairing channel in the cement ring and a gas channeling channel communicated with the repairing channel in the cement ring through holes under the blocking of the first setting device;

And cutting off the first setting device by using a well repairing tool, lifting the tool to the ground, and forming a plugging body after the metal fluid is cooled so as to realize repairing the annular space with pressure.

The technical scheme provided by the embodiment of the invention has the beneficial effects that at least:

The tool for repairing the annular space with pressure comprises a body, a drilling component, an opening component, a repairing component and a first setting device, wherein the drilling component, the opening component, the repairing component and the first setting device are sequentially arranged on the body from top to bottom, the opening component is used for carrying out perforation treatment on a sleeve, the drilling component is used for drilling a cement sheath through a perforation to form a repairing pore channel, meanwhile, the device activates heating fuel through a starter to heat and melt a fusible metal block in a storage mechanism to form metal fluid so as to replace the sealing function of an original cement sheath, compared with the existing mode that cement sheath or resin is used as a plugging material, the time for cooling and solidifying the fusible metal from a liquid state to form the metal plugging body is short, and the metal plugging body established after cooling of the fusible metal has good sealing performance, high bearing capacity and good corrosion resistance.

Meanwhile, compared with the existing method of perforating the cement sheath, the tool for repairing the annular space with pressure provided by the embodiment of the invention has the advantages that the universal shaft and the drilling bit of the drilling assembly can create a large-volume channel on the cement sheath, after the drilling bit touches the sleeve after drilling for a period of time in the cement sheath, the hardness of the sleeve is far greater than that of cement, the bit and the universal shaft turn to continuously drill between the sleeves at two sides to form a spiral repairing channel, more and more gas channeling channels are communicated with the channel along with the deep drilling bit in the cement sheath, the capacity of filling the gas channeling channels with plugging materials can be improved, and the repairing effect of the annular space with pressure of the cement sheath is further improved.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims thereof as well as the appended drawings.

The technical scheme of the invention is further described in detail through the drawings and the embodiments.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate the invention and together with the embodiments of the invention, serve to explain the invention. In the drawings:

FIG. 1 is a schematic diagram of a tool for repairing annular space with pressure in an embodiment of the invention;

FIG. 2 is a schematic view showing a partial structure of a tool for repairing annular space with pressure in a state of a casing hole in an embodiment of the invention;

FIG. 3 is a schematic view showing a partial structure of a tool for repairing annular space with pressure in a cement-drilling state according to an embodiment of the present invention;

FIG. 4 is a schematic view of a partial structure of a tool for repairing annular void with pressure in a metal fuse plugging state according to an embodiment of the present invention;

Fig. 5 is a side view of a drill set head crushed set in an embodiment of the invention.

Reference numerals illustrate:

1. A body; 2, a drilling assembly, 3, an opening assembly, 4, a repairing assembly, 5, a first setting device, 6, a second setting device, 7, a third setting device, 8, a production casing, 9, a technical casing, 10, and a cement sheath;

21. cardan shaft, 22, drilling bit, 23, guider, 24, fluid flow channel, 25, turbine, 31, drilling bit, 32, screw motor, 33, hydraulic device, 34, drill rod, 41, heater, 42, storage mechanism, 43, metal block, 44, starter, 45, screen, 102, second cavity.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected via an intervening medium, or in communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

In the prior art, aiming at the problem of annular pressure caused by sealing failure of a cement ring, a sleeve and the cement ring are generally opened in a perforation mode, plugging materials are injected to repair the cement ring on the basis of damaged cement ring, but the pore canal formed by perforation cannot enable the plugging materials to flow into a channeling channel efficiently and in a large volume, and the problems of insufficient bearing strength, poor air tightness and the like of the plugging body are possibly caused.

Therefore, in order to solve the problems of poor sealing effect, long construction period, high difficulty, high single well operation cost and the like of the prior art in a mode of treating the sealing failure of the cement sheath, the embodiment of the invention provides a tool and a method for repairing annular pressure, so as to treat the annular pressure problem generated after the sealing failure of the cement sheath of the old well and realize the reconstruction of the integrity of the well shaft of the old well.

The embodiment of the invention provides a tool for repairing annular space with pressure, which is shown by referring to figures 1 to 4 and comprises a body 1, a drilling component 2, an opening component 3, a repairing component 4 and a first setting device 5, wherein the drilling component 2, the opening component 3, the repairing component 4 and the first setting device are sequentially arranged on the body 1 from top to bottom;

wherein the opening assembly 3 is used for opening holes to the production casing 8;

A drilling assembly 2 for drilling a cement sheath 10 between a production casing 8 and a technical casing 9 through an aperture to form a repair tunnel;

The repair assembly 4 includes a heater 41 and an actuator 44;

the heater 41 is disposed in a first cavity (not shown) of the body 1, and forms a storage mechanism 42 with the body 1;

the storage mechanism 42 is used for storing the fusible metal block 43 and is communicated with the outside, the heater 41 is used for containing heating fuel, the starter 44 is arranged at the top end of the heater 41 and used for starting and activating the heating fuel based on a starting signal transmitted from the outside, and then the fusible metal block 43 is fused by the heating fuel to form metal fluid;

The first setting device 5 is used to fix the tool position and allow the metal fluid flowing from the reservoir 42 to pass through the hole into the repair channel under the barrier of the first setting device 5.

According to the tool for repairing annular space with pressure, provided by the embodiment of the invention, the low-melting-point metal in the tool is melted through the heater 41, so that the tool replaces the sealing effect of the original cement ring 10, the time required for forming a metal plugging body by cooling and solidifying the fusible metal from a liquid state is short, the metal plugging body with good sealing property and high pressure bearing capacity can be built in the annular space, the repairing time of annular space with pressure problem can be shortened, and the repairing effect of annular space with pressure is improved.

The specific shape of the fusible metal block 43 is not particularly limited in the embodiment of the present invention, and may be a monolithic structure, a multi-block structure with different sizes, a metal ball structure with different sizes, or the like, which may be specifically selected according to actual needs.

In one embodiment, the fusible metal used as the plugging material in the present embodiment may be specifically a low-melting-point and high-strength metal, and the low-melting-point metal may take only a few minutes to form a metal plugging body by cooling and solidifying from a liquid state, wherein the fusible metal in the present embodiment may be specifically, for example, a binary eutectic alloy of bismuth and germanium, a binary eutectic alloy of bismuth and copper, a binary eutectic alloy of bismuth and tin, or a binary eutectic alloy of bismuth and silver. The present inventors found in the study that the above alloys have a melting point of about 95 ℃ to 240 ℃ and the alloys expand by 1% to 3.3% when solidified from liquid to solid, which makes the alloys fully fit the surrounding environment, firmly seal specific spaces in an interference fit, and well meet the sealing requirements of the cement ring 10.

In one embodiment, the heating fuel contained in the heater 41 may be thermite powder and thermite drug block;

The thermite block is stacked in the heater 41, thermite powder is arranged on the top of the thermite block to excite the thermite powder through the starter 44 to generate high temperature to ignite the thermite block, and the thermite powder is relatively sensitive and is arranged on the top of the fuel cavity of the heater 41, so that the thermite powder can be excited through small current ignition, the high temperature generated by the thermite powder continuously ignites the thermite block adjacent to the thermite block, and then the thermite block stacked in the thermite block starts self-propagating reaction from the upper part. A storage mechanism is provided in the annulus between the heater 41 and the body 1 for storing the low melting point metal pellets, and since the thermite reaction is at a high temperature of about 1200 ℃, the thermite is used as a heating fuel, and the thermite continuously releases heat to melt all of the low melting point metal pellets outside the heater 41. Accordingly, the heater 41 in the present embodiment is a thermite reaction heater 41.

Further, the actuator 44 of the present embodiment is connected to a cable through which an electric signal is transmitted to control the actuator 44 to activate the fuel inside the heater 41.

In one embodiment, referring to fig. 1 and 4, the lower end of the first chamber is provided with a screen;

Wherein, a storage mechanism 42 is formed among the body 1, the heater 41 and the screen 45, the storage mechanism 42 is communicated with the outside through the screen 45, and correspondingly, the metal fluid flows out of the storage mechanism 42 through the screen 45.

In one embodiment, referring to fig. 1 and 2, the tapping assembly 3 is disposed in the second cavity 102 of the body 1, and includes a tapping drill 31, a drill rod 34, a hydraulic device 33, and a screw motor 32;

Wherein, a window for the drill rod 34 to extend out is arranged on the side wall of the body 1;

One end of the drill rod 34 is connected with the perforating drill bit 31, the other end is connected with a piston rod of the hydraulic device 33 to drive the drill rod 34 to move through the hydraulic device 33, and the side wall of the drill rod 34 is meshed with a screw gear of the screw motor 32 to drive the drill rod 34 to rotate through the screw motor 32.

In this embodiment, when the casing hole opening operation is required, the screw motor 32 and the hydraulic device 33 receive external control signals to start the operation, the hole drill 31 performs casing hole opening through the weight on bit and torque provided by the downhole screw motor 32 and the hydraulic device 33, after hole opening is finished, based on the received external control signals, the screw motor 32 stops working, oil in a hydraulic cylinder of the hydraulic device 33 returns to retract a piston rod, and the drill rod 34 is pulled back at the same time, so that the hole drill 31 is reset. Wherein, the casing perforating assembly 3 needs to make a plurality of holes in different directions of different well depths, and particularly can realize a plurality of perforating operations by controlling the rotary positioning and setting of the tool for a plurality of times through the ground.

Further, the drill bit 31 may be a spade drill bit, and the drill bit material is a composite hard alloy formed by compounding hard metal and high-speed steel, so that the phenomenon of tooth breakage during the hole opening is reduced, and the hole opening success rate and the service life of the drill bit are improved. Wherein, when the production casing 8 is perforated, the rotating speed is selected to be 150-200r/m, the drilling pressure is 60-80KN, and at the moment, 10-20 minutes are needed for drilling through the N80 and P110 casings by using the perforating drill bit 31.

In one embodiment, referring to fig. 1 and 3, the upper end surface of the body 1 is provided with at least one fluid inlet, and the side wall is provided with a fluid outlet corresponding to the fluid inlet;

the drilling assembly 2 comprises a fluid flow passage 24 for communicating a fluid inlet and a corresponding fluid outlet, a universal shaft 21 and a turbine 25 which are arranged in the fluid, wherein the front end of the universal shaft 21 is connected with a drilling bit 22;

The turbine 25 is sleeved on the universal shaft 21 to drive the universal shaft 21 and the drilling bit 22 to move under the hydraulic action, and the cement sheath 10 is drilled through the holes to form a repairing hole.

The tool provided by the embodiment is used for controlling the bit to reset after the casing is perforated, removing the tool setting and moving the whole tool downwards for a certain distance, enabling the drilling bit 22 of the drilling assembly 2 to be aligned with the perforated hole, and after the tool is re-set, sending the universal shaft 21 into the cement sheath 10 through the perforation for cement drilling. In the drilling assembly 2 of this embodiment, after the drilling bit 22 is driven by the cardan shaft 21 to drill in the cement sheath 10 for a period of time, the casing hardness is far greater than that of cement, so that the drilling bit 22 and the cardan shaft 21 turn, and continue to drill between the casings at two sides, so as to create a large-volume pore channel on the cement sheath 10, and as the bit goes deep in the cement sheath 10, more and more gas channeling channels are communicated with the pore channel, so that the capability of filling the gas channeling channels with plugging materials can be improved.

Further, the universal shaft 21 in the present embodiment may employ a cross-shaft type rigid universal joint or a ball and socket type universal joint for transmitting weight on bit and torque. Specifically, the cross-shaft type universal joint consists of a cross shaft, two universal joint forks, a needle bearing and the like, and holes on the two universal joint forks are respectively sleeved on two pairs of shaft journals of the cross shaft. In order to reduce friction loss and improve transmission efficiency, a needle bearing consisting of a needle and a sleeve is arranged between the cross axle journal and the universal joint fork hole. The sleeve is fixed on the universal joint fork by the screw and the bearing cover, and the screw is locked by the locking plate so as to prevent the bearing from falling out of the universal joint fork under the action of centrifugal force. Thus, when the driving shaft rotates, the driven shaft can rotate along with the driving shaft and can swing in any direction around the center of the cross shaft.

Optionally, the inside of the universal joint of the universal shaft 21 may be provided with flow channels which are mutually communicated, and in the process of drilling cement, fluid can flow out through the joint between the adjacent universal joints, the pressure difference of the fluid washes the pore canal wall, and the debris of the cement is discharged, and simultaneously lubrication is provided for self, so that friction resistance is reduced.

The surface material and structure of the cardan shaft 21 are not particularly limited, and may be selected according to practical needs to reduce friction resistance during rotary drilling.

Specifically, the turbine 25 in this embodiment is composed of blades, a disk, a casing, and the like. Among these, the blades are the most critical parts, the design and manufacturing quality of which directly affects the performance and service life of the turbine 25, and the disk plays a role of supporting and rotating the blades, bearing the centrifugal and inertial forces of the blades. The housing then acts as a seal and guide to ensure that the working fluid flows within the turbine 25. Further, the turbine 25 blades may be hollow to reduce the mass and inertia of the blade. The cross-section of the blade is tapered to reduce aerodynamic drag and inertial forces of the blade. The surface of the blade adopts streamline design to reduce the friction resistance and the profile resistance of the fluid. The turbine 25 wheel disc is made of steel, and has a plate shell structure or a turbine 25 wheel structure, and the surface is subjected to high-temperature alloy surface treatment so as to improve heat resistance and fatigue resistance.

In one embodiment, referring to FIGS. 1 and 3, the fluid flow path 24 may include a straight section, a tapered section, and a curved section connected in sequence from top to bottom;

the direct current section is connected with one end with a larger diameter of the conical section, and the bending section is connected with one end with a smaller diameter of the conical section;

the turbine 25 is in threaded engagement with the inner wall of the dc section, and the conical section is used to limit the downward travel of the turbine 25.

The lower part of the fluid flow channel 24 of the embodiment of the invention is provided with the conical section and the bending section, and the structure can also guide the movement of the universal shaft 21, so that the phenomenon of winding and the like deviating from the movement direction in the rotation process of the universal shaft 21 is avoided, and the drilling effect on the cement sheath 10 is influenced. The number and distribution of the fluid flow channels 24 are not particularly limited, and for example, 4 fluid flow channels 24 may be provided, and the 4 fluid flow channels 24 are uniformly provided at the upper portion of the body 1. The turbine 25 wheel disc is locked with the universal shaft 21, after the high-pressure fluid is pumped into the ground, the upper and lower pressure difference acts to enable the impeller and the wheel disc of the turbine 25 to rotate, the universal shaft 21 is driven to rotate, the shell of the turbine 25 descends under the action of the inclined threads in the rotating process, required drilling pressure and torque are provided for drilling, when the turbine 25 moves to the conical section of the fluid flow channel, the conical section is blocked, namely, the universal shaft stretches out to stop moving forwards, and accordingly, the pumping of the high-pressure fluid can be controlled to stop according to the change of the fluid medium parameters (such as pressure, fluid flow rate and the like) detected by a wellhead detecting instrument. Preferably, when the fluid flow passages 24 are provided in two or more, the fluid flow passages 24 are not communicated with each other.

In one embodiment, the drill bit 22 may be embodied as a diamond-impregnated bit with a nozzle in the center of the bit, wherein fluid flowing through the fluid flow channels 24 may act as a cooling fluid to cool the bit and assist in breaking the cement sheath 10 during the drilling of the cement sheath 10.

Further, when the turbine 25 is driven to move the universal shaft 21 and the drilling bit 22 under the hydraulic action, the high-pressure fluid pumped from the ground can be specifically 15% -30% hydrochloric acid solution, the high-pressure fluid enters the fluid flow channel 24 under the preset pressure (for example, 20 MPa), the turbine 25 is driven to rotate, after the acid solution flows into the repaired pore channel in the cement sheath 10, the cement stone is corroded to enlarge the pore channel volume, and the acid solution sprayed from the drilling bit 22 can soften the cement stone, so that the mechanical drilling speed is improved.

All working components working in an acid liquid environment are required to be sprayed with an anti-corrosion coating, a common anti-corrosion treatment means in the prior art is a chromium plating nickel plating process and a special anti-corrosion coating process, the anti-corrosion coating used in the general oil field is prepared by adding other organic polymer anti-corrosion resins such as ketoaldehyde and the like into epoxy phenolic resin as a main component, the coating is resistant to chemical medium, and the coating is hard and has good adhesive force, excellent anti-corrosion performance, salt water resistance and oil resistance, and is suitable for protecting and preventing the surfaces of various metal structure equipment. In this embodiment, therefore, the body 1, the cardan shaft 21, the drill bit 22, the turbine 25, the fluid flow passage 24 and the like all need to be coated with the anti-corrosive coating.

Further, the diameter of the hole-opening drill 31 of the tool provided in this embodiment needs to be larger than the diameter of the drill bit 22, preferably, the size of the hole formed after the hole opening is much larger than the diameter of the drill bit 22, so that after the subsequent assembly and disassembly assembly is moved down, the drilling can be started without precisely aligning the casing hole, wherein the specific sizes of the hole-opening drill 31 and the drill bit 22 are not limited, and can be selected according to practical needs, for example, the diameter of the hole-opening drill 31 can be about 40mm, and the diameter of the drill bit 22 can be about 10mm.

In one embodiment, referring to fig. 1 and 3, a guide 23 may be further provided on the sidewall of the body 1;

the inner bore of the guide 23 communicates with the flow passage to guide the movement of the cardan shaft 21.

Further, the center line of the inner hole of the guide 23 may be disposed at a predetermined angle with the center line of the body 1.

The guide 23 may be a fixed initial orientation for the cardan shaft 21 and the drill bit 22 to ensure that the drill bit can be aligned with the casing hole, and the effective length of vertical drilling is small due to the thin cement sheath 10, so the guide 23 may be provided with an inclination angle to allow the drill bit to drill into the cement sheath 10 at an angle, and the finally formed tunnel may be spiral, as shown in fig. 5, the formed tunnel may have a larger volume, which is advantageous for the inflow and plugging of subsequent molten metal.

In one embodiment, referring to FIG. 1, the tool provided by the embodiment of the invention further comprises a second setting device 6 and a third setting device 7;

The second setting device 6 is disposed at the upper end of the body 1, and the third setting device 7 is disposed between the opening assembly 3 and the repairing assembly 4.

In particular, the second setting device 6 and the third setting device 7 are used for setting tools when the casing is perforated and the cement sheath 10 is drilled to form a repairing hole, wherein the first setting device 5, the second setting device 6 and the third setting device 7 can be specifically spring bridge plugs, and the process of setting and unsetting tools by the first setting device 5, the second setting device 6 and the third setting device 7 can refer to the prior art, and the embodiment of the invention is not limited in this way.

In one embodiment, an implementation of the tool provided by the embodiment of the present invention is exemplarily described as follows:

(1) Firstly, the optimal repairing section of the gas channeling of the cement sheath 10 is judged by using a logging technology, then the tool is lowered to a pre-opening Kong Jingduan through an oil pipe, and the tool is set by using the second setting device 6 and the third setting device 7 so as to fix the position of the tool.

(2) The screw motor 32 and hydraulic means 33 of the tapping assembly 3 are activated to provide torque and weight on bit 31, mill the hole in the casing and effect tapping of a plurality of holes at different depths and orientations by surface controlled rotation or lowering of the tool.

(3) After completion of casing perforation, the setting of the tool is released and the tool is moved down, the drilling assembly 2 is aligned to the perforated position, the position of the drill bit 22 of the drilling assembly 2 is brought into correspondence of the height and orientation of the perforation relative to the perforation formed, and the tool is set using the second setting device 6 and the third setting device 7.

(4) The turbine 25 drives the universal shaft 21 and the drill bit 22 to drill in the cement sheath 10 under the action of pressure difference by pumping high-pressure fluid from the ground, and the guide 23 is used for providing preliminary orientation for the drill bit 22, so that the universal shaft 21 continuously enters in the drilling process, and a repairing pore canal is formed in the cement sheath 10.

(5) The tool setting is released, the whole pipe string is lifted to lift the repairing assembly 4 to the well section to be plugged, the first setting device 5 is used for setting the tool, the metal block 43 in the storage mechanism 42 is heated and melted, liquefied metal flows out through the screen 45 and flows into the pore canal and the air channeling channel in the cement sheath 10 through the holes, then the first setting device 5 is sheared by the well repairing tool to be lifted and recovered integrally, and the metal is cooled to form a high-strength plugging body.

Based on the same inventive concept, the embodiment of the invention also provides a method for repairing annular space with pressure based on the tool for repairing annular space with pressure, which comprises the following steps:

lowering the tool to a first preset position in the production casing, and after setting the tool, opening at least one hole in the production casing by using the opening assembly;

after the hole opening treatment of the sleeve is completed, the tool setting is released, the tool is controlled to move downwards to a second preset position, the tool is set, and the drilling component is utilized to drill out the cement sheath through the hole to form a repairing hole;

after the drilling of the repairing hole channel is completed, the tool setting is released, the tool is lifted to a third preset position, the first setting device is used for fixing the tool position, a heating component is used for heating and melting a fusible metal block in the storage mechanism to form metal fluid, and after the metal fluid flows out of the storage mechanism, the metal fluid flows into a repairing channel in the cement ring and a gas channeling channel communicated with the repairing channel in the cement ring through holes under the blocking of the first setting device;

And cutting off the first setting device by using a well repairing tool, lifting the tool to the ground, and forming a plugging body after the metal fluid is cooled so as to realize repairing of annular space with pressure.

The specific positions of the first preset position, the second preset position and the third preset position can be set according to the condition of the well bore to be repaired, and the embodiment of the invention is not particularly limited, wherein the first preset position is specifically a preset opening position in the cement sheath gas channeling optimal repair section determined by using a logging technology.

The specific process of the method for repairing annular space with pressure based on the tool for repairing annular space with pressure in the above embodiment is described in detail in the embodiment of the tool for repairing annular space with pressure, which will not be described in detail herein.

The embodiment of the invention provides an annulus pressure metal repair tool and method, which are used for removing a cement sheath with a certain thickness and a seal failure and replacing the cement sheath with a metal plugging body. The annular pressure repairing valve is characterized in that a tool body is firstly put into a preset position, a drilling bit is used for drilling a sleeve after the tool is set, the tool can be subjected to multiple rotation positioning and setting through ground control according to requirements, multiple drilling is realized, then the anchoring of the tool is released, the tool is moved downwards, the drilling bit of a drilling assembly is aligned to the drilling position, a cardan shaft and the drilling bit drill in a cement sheath between a technical sleeve and a production sleeve to form a repairing pore channel, finally low-melting-point high-strength metal stored at the lower end of the tool is used as a plugging material, the metal is heated, melted and extruded into an annulus underground, and a high-strength plugging body is formed after cooling, so that the annular pressure long-term effective plugging is realized.

It should be understood that the specific order or hierarchy of steps in the processes disclosed are examples of exemplary approaches. Based on design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged without departing from the scope of the present disclosure. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

In the foregoing detailed description, various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments of the subject matter require more features than are expressly recited in each claim. Rather, as the following claims reflect, invention lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate preferred embodiment of this invention.

The foregoing description includes examples of one or more embodiments. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned embodiments, but one of ordinary skill in the art may recognize that many further combinations and permutations of various embodiments are possible. Accordingly, the embodiments described herein are intended to embrace all such alterations, modifications and variations that fall within the scope of the appended claims. Furthermore, as used in the specification or claims, the term "comprising" is intended to be inclusive in a manner similar to the term "comprising," as interpreted when employed as a transitional word in a claim. Furthermore, any use of the term "or" in the specification of the claims is intended to mean "non-exclusive or".

Claims (13)

1. The tool for repairing annular space with pressure is characterized by comprising a body, a drilling assembly, an opening assembly, a repairing assembly and a first setting device, wherein the drilling assembly, the opening assembly, the repairing assembly and the first setting device are sequentially arranged on the body from top to bottom;

the perforating assembly is used for perforating the production sleeve;

The drilling assembly is used for drilling the cement sheath through the hole to form a repairing pore canal;

The repair assembly includes a heater and a starter;

The heater is arranged in the first cavity of the body, and a storage mechanism is formed between the heater and the body;

The device comprises a storage mechanism, a heater, a starter, a heating device and a control unit, wherein the storage mechanism is used for storing a fusible metal block and is communicated with the outside;

The first setting device is used to fix the tool position and allow the metal fluid flowing from the reservoir to enter the repair channel through the aperture under the barrier of the first setting device.

2. The tool of claim 1, wherein the upper end surface of the body is provided with at least one fluid inlet, and the side wall is provided with a fluid outlet corresponding to the fluid inlet;

the drilling assembly comprises a fluid flow passage for communicating the fluid inlet with a corresponding fluid outlet, a universal shaft and a turbine which are arranged in the fluid, and a drilling bit connected to the front end of the universal shaft;

the turbine is sleeved on the universal shaft, so that the universal shaft and the drilling bit are driven to move under the action of hydraulic pressure, and the cement sheath is drilled through the hole to form a repairing pore canal.

3. The tool of claim 1 wherein the fusible metal mass comprises a binary eutectic alloy of bismuth and germanium, a binary eutectic alloy of bismuth and copper, a binary eutectic alloy of bismuth and tin, or a binary eutectic alloy of bismuth and silver.

4. The tool of claim 1 wherein the heating fuel comprises thermite powder and thermite mass;

The thermite medicine block is stacked in the heater, and the thermite powder is arranged at the top of the thermite medicine block, so that the thermite powder is excited by the starter to generate high-temperature ignition for the thermite medicine block.

5. The tool of claim 1, wherein a screen is provided at a lower end of the first cavity, the storage mechanism being in communication with the outside through the screen;

accordingly, the metal fluid flows out of the storage mechanism through the screen.

6. The tool of claim 2, wherein the fluid flow path comprises a straight section, a tapered section and a curved section connected in sequence from top to bottom;

The direct current section is connected with one end of the conical section with larger diameter, and the bending section is connected with one end of the conical section with smaller diameter;

the turbine is in threaded engagement with the inner wall of the direct current section, and the conical section is used for limiting the downward movement of the turbine.

7. A tool as claimed in claim 2, wherein the joint of the cardan shaft is internally provided with flow passages communicating with each other;

The drilling bit is a diamond-embedded bit, and a nozzle is arranged in the center of the drilling bit.

8. The tool of claim 1, wherein the tapping assembly is disposed within the second cavity of the body and comprises a tapping drill, a drill rod, a hydraulic device, and a screw motor;

a window which can be used for the drill rod to extend out is formed in the side wall of the body;

One end of the drill rod is connected with the perforating drill bit, the other end of the drill rod is connected with a piston rod of a hydraulic device so as to drive the drill rod to move through the hydraulic device, and the side wall of the drill rod is meshed with a screw gear of the screw motor so as to drive the drill rod to rotate through the screw motor.

9. The tool of claim 8, wherein the diameter of the hole-forming drill bit is greater than the diameter of the drill bit.

10. The tool of claim 1, wherein the body sidewall is further provided with a guide;

the inner hole of the guide is communicated with the flow channel so as to guide the movement of the universal shaft.

11. The tool of claim 10, wherein a centerline of the pilot bore is disposed at a predetermined angle from a centerline of the body.

12. The tool of any one of claims 1-11, further comprising a second setting device and a third setting device;

The second setting device is arranged at the upper end of the body, and the third setting device is arranged between the opening assembly and the repairing assembly.

13. A method of repairing an annulus with pressure, based on a tool according to any of claims 1-11, comprising:

lowering the tool to a first preset position in the production casing, and after setting the tool, opening at least one hole in the production casing by using the opening assembly;

After the perforated hole of the sleeve is processed, the tool setting is released, the tool is controlled to move downwards to a second preset position, the tool is set, and a drilling component is utilized to drill out the cement sheath through the perforation to form a repairing pore canal;

After the drilling of the repairing hole channel is completed, the tool setting is released, the tool is lifted to a third preset position, the first setting device is used for fixing the tool position, a heating component is used for heating and melting a fusible metal block in the storage mechanism to form a metal fluid, and after the metal fluid flows out of the storage mechanism, the metal fluid flows into a repairing channel in the cement ring and a gas channeling channel communicated with the repairing channel in the cement ring through holes under the blocking of the first setting device;

And cutting off the first setting device by using a well repairing tool, lifting the tool to the ground, and forming a plugging body after the metal fluid is cooled so as to realize repairing the annular space with pressure.